• 한국정보통신학회논문지
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• 제15권6호
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• pp.1386-1390
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• 2011

IEEE 802.11 MAC은 노드들간에 매체 접근을 제어하기 위해 DCF를 사용한다. 하지만 DCF 자체로는 실시간 데이터 전송에 필요한 QoS 요구사항을 만족시킬 수 없다. 이를 보완하기 위해 802.11 MAC에서 제공되는 DCF 기능을 수정하여 QoS를 제공하는 다양한 기법들이 나왔다. 본 논문에서는 DCF 기능을 향상시키기 위해 (m,k)-firm 기법을 이용하면서 IEEE 802.11에 근거한 (m,k)-collision 기법을 제시했다. 제시된 기법은 노드에서 발생되는 충돌 횟수에 따라 서로 다른 CW 값을 할당한다. 시뮬레이션 결과 제시된 기법이 DCF의 처리율 향상에 도움을 주고 있다는 것을 보여준다.

• 한국정보통신학회논문지
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• 제18권6호
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• pp.1435-1440
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• 2014

WSN내의 노드들은 한정된 에너지를 지녔다. 따라서 각 노드들의 채널에 대한 접근을 효율적으로 제어하는 것이 채널 활용성과 에너지 소모에 중요한 역할을 수행한다. 본 논문에서는 WSN에서 각 노드에서의 에너지 효율성을 높이기 위해 하이브리드 TDMA/CSMA MAC을 위한 우선순위 기반 타임 슬롯 할당 프로토콜을 제안한다. 제안된 프로토콜은 TDMA와 CSMA 기법의 장점을 활용함과 동시에 (m,k)-firm 기법을 이용하여 채널 접근의 우선권을 제공하였다. 성능 평가를 위해 다양한 노드 수의 변화에 따른 시뮬레이션을 수행하였고, S-MAC과 비교하여 평균 지연시간과 패킷 전송률에서 많은 향상을 보여주었다.

• 산업경영시스템학회지
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• 제30권1호
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• pp.15-24
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• 2007

This paper attempts to identify empirically whether the certification of Quality Management System affects positively to firm performance using the sample sets of 200 SMEs in Korea who have adopted ISO 9000 majoring in the domestic markets as well as the overseas markets. The empirical study has been done on the assumptions and the hypothesis that the certification itself can conceptually and practically be considered an effective tool to improve the level of standardization of quality management system, and it would result in higher productivity and good corporate image by enabling firms to strengthen up their capabilities to achieve competitive advantage. The empirical findings show that the ISO 9000 has positively contributed to not only obtaining competitive advantage but also bringing about a superior firm performance as it would be, making sure that the certification itself would be used as a powerful tool for good management. This study also pinpoints that the success/failure in introducing & adopting the certification depends highly upon the managers' interests and concerns, especially the CEO's.

• 산경연구논집
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• 제14권7호
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• pp.9-18
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• 2023

Purpose: The ability of a firm to acquire resources through marketing networks is crucial for its competitiveness. Nonetheless, the influence of these networks on the performance of a firm's innovation is still uncertain, particularly in the face of environmental uncertainty. This research investigates the impact of marketing networks, specifically network embeddedness and structural holes, on the performance of innovation in situations characterized by environmental uncertainty. Research design, data and methodology: The empirical examination was carried out within the framework of internal network entities, specifically the manufacturer-supplier-sub supplier relationships, involving the primary suppliers of a Korean engineering firm. Construct measures utilized in this study were derived from existing measures and prior research. A questionnaire survey was conducted with a major first-tier supplier of a Korean engineering firm. Proposed hypotheses were tested using structural equation modeling. Results: The survey findings suggest that only network embeddedness has an impact on the perception of major first-tier suppliers regarding the buyer's innovation performance. Conclusions: To strengthen the empirical evidence regarding the effects of marketing networks on innovation performance, future research should take into account cultural factors such as collectivism, which is indicative of the distinctive business-to-business marketing relationships observed in the Korean context.

• Journal of information and communication convergence engineering
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• 제8권2호
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• pp.212-218
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• 2010

In wireless sensor networks (WSNs), both efficient energy management and Quality of Service (QoS) are important issues for some applications. For creating robust networks, real-time services are usually employed to satisfy the QoS requirements. In this paper, we proposed a hierarchical real-time MAC (medium access control) protocol for (m,k)-firm constraint in wireless sensor networks shortly called HRTS-MAC. The proposed HRTS-MAC protocol is based on a dynamic priority assignment by (m,k)-firm constraint. In a tree structure topology, the scheduling algorithm assigns uniform transmitting opportunities to each node. The paper also provides experimental results and comparison of the proposed protocol with E_DBP scheduling algorithm.

• Industrial Engineering and Management Systems
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• 제13권1호
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• pp.15-28
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• 2014

Evaluation of the implementation and performance of a firm's green supply chain management (GSCM) is an ongoing process. Balanced scorecard is a multi-criteria evaluation concept that highlights implementation and performance measures. The literature on the framework is abundant literature but scarce on how to build a hierarchical framework under uncertainty with dependence relations. Hence, this study proposes a hybrid approach, which includes applied interpretive structural modeling to build a hierarchical structure and uses the analytic network process to analyze the dependence relations. Additionally, this study applies the fuzzy set theory to determine linguistic preferences. Twenty dependence criteria are evaluated for a GSCM implemented firm in Taiwan. The result shows that the financial aspect and life cycle assessment are the most important performance and weighted criteria.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2015년도 춘계 학술논문 발표대회
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• pp.115-116
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• 2015

Recently, most of the construction companies is being degraded due to the overall construction recession profitability. Among them, order quantity of the architectural and engineering firms are trend to decrease except for large companies over a certain size. In particular, small companies are facing more difficulties. This study was conducted expert interview method to extract the main cause of profitability degradation of a small-sized design engineering companies. And, we are proposes a critical influence factors through survey about extracted factors. The results of this study are expect to help the competitiveness of architectural design firm.

• 산업경영시스템학회지
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• 제30권1호
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• pp.48-58
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• 2007

For a sustainable development, the resources circulation system should be established and required alternative logistics area of enterprises. In this paper, we are to suggest a direction through analysis effects, and reduce, recycle, reuse factor of transportation, material handling, packing, information, management in logistics function, and effects of logistics organization on Firm Performance. We found significant correlations between the constructs extracted above, and between the constructs and firm's performance. This study was conducted with the subjects of manufacturing enterprises with concurrent reviews of literature and statistical analysis, and the meaning of this study would be the analysis of the influencers of the resources circulation system.

• 국제학술발표논문집
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• The 2th International Conference on Construction Engineering and Project Management
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• pp.583-592
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• 2007

Entrepreneurship scholars have defined Corporate Entrepreneurship (CE) in many ways. Generally, works from these scholars had discussed on the common aspects of CE, benefits of CE, types of CE and ways to cultivate and design CE for companies. These scholars also developed models of CE to construct a framework for mapping CE research. From here, the present writers have presented a proposed framework to see how far the factors of CE, their business strategy and external environment influenced the developers' firm performance in housing development industry. However, this is just the initial stage of the study and the model needs to be revised before it can be tested in the field.

• Management Science and Financial Engineering
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• 제17권1호
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• pp.45-63
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• 2011

The aim of this paper is to consider the process of supplying trained workers with knowledge and skills for upcoming business opportunities and the process of training apprentices to be prepared to meet future demands in an IT service firm. As the demand for new workers fluctuates, a firm should employ a buffer workforce such as apprentices or interns. However, as a result of rapid business development, the capacity of the buffer may be exceeded, thus requiring the company to recruit skilled workers from outside the firm. Therefore, it is important for a firm to map out a strategy for manpower planning so as to fulfill the demands of new business and minimize the operation costs related to training apprentices and recruiting experienced workers. First, this paper analyzes the supply and demand of workers for the IT service in a knowledge-intensive field. It then presents optimal human resource planning strategies via the familiar method of stochastic process. Also, we illustrate that our model is applied to the human resource planning of an information security service firm in South Korea.